Refacing machine



Nov. 10, 1959 Filed July 20, 1955 A. A. STUDLER 2,911,765.

REFACING MACHINE 5 Sheets-Sheet 1v" I970. @71 I070 [97d INVENTOR.

- BY AM.

Nov. 10, 1959 A. A. STUDLER REFACING MACHINE 5 Sheets-Sheet 2 Filed July 20. 1953 IN VEN TOR.

fiffae/H/'f Nov. 10, 1959 A. A. STUDLER REFACING MACHINE 5 Sheets-Sheet 3 Filed July 20, 1953 wm R Nov. 10, 1959 A. A. STUDLER 2,911,765

, REFACING MACHINE Filed July 20. 1953 5 Sheets-Sheet 5 fiUQZE 1 7. 577/0459,

.IV VEN TOR.

United States Patent REFACING MACHINE Aurele A. Studler, Glendale, Calif.; Clara B. Studler, executrix of said Aurele A. Studler, deceased Application July 20, 1953, Serial No. 369,060

22 Claims. (Cl. 51-123) This invention relates to refacing of machine parts, and while the invention is applicable in the construction of machines for refacing any kind of a machine part, it is particularly useful for refacing the seat faces of valves of the poppet type employed extensively in the industrial arts and most extensively in engines of all kinds.

In conducting such a refacing operation it is common practice to employ a rotary grinding wheel having an abrasive face against which the face to be refaced is held, and while so held the part being refaced is caused to travel to and fro across the abrading face of the grinder wheel. In doing this it also is the practice to give the machine part a travel that will cause it to lap over the edges of the abrasive face. This makes for uniform wear on the abrasive face, and increases the period of usefulness of the grinder wheel after each time that the face of the wheel has been redressed.

And as the faces of machine parts that must be refaced vary considerably in width it is necessary to provide means in such mechanisms for quickly setting it to alter the length of travel that is imparted to the face being refaced.

And it is also frequently required to change at will the location of the zone of travel of the part being ground, on the abrasive face.

Another object of the invention is to provide a chuck of improved construction that will facilitate the automatic ejection of a machine piece that has just been refaced, from the chuck, and leaving the chuck in its open position ready to receive the next article that is to be refaced.

Another object of the invention is to provide means associated with the chuck for effectively sealing the chuck against the entrance of any detritus produced incidentally to the operation. This is most advantageous because in the refacing of some articles such as valves, each valve must be held precisely in position and rotated with precision about its own axis in the refacing operation.

Further objects of the invention will be evident from a careful reading of the specification and accompanying drawing disclosing this invention.

In the drawing:

Figure 1 is an end view of a refacing machine embodying this invention.

Figures 2a and 2b are companion views that should be examined together. They show the machine in plan with some parts shown in horizontal section. Figure 2a shows the chuck holding a poppet type valve the'disc of which is held against the abrasive face of a rotary grinder; it also illustrates the means for enabling the carriage for the chuck that carries the machine part to be moved at will to apply the surface being refaced to the abrasive face of the grinder, and in dotted lines illustrates means for controlling the amount of travel of the surface being refaced; also the means for shifting the location of the travel.

Figure 3 is a longitudinal section taken in a horizontal plane through the chuck that holds the part being reice means employed for controlling fluid flow to the mechanism for effecting the ejection of the machine part from the chuck, that is brought into action by the movement of the carriage that withdraws the machine part from the abrasive surface.

Figure 4a is a vertical section taken on the line la-4w of Figure 6, passing through a rocker arm, and further illustrating details of its connection to a block-form saddle with which the rocker arm has a sliding relation. Figure 4a further illustrates the connection between this block and an adjusting screw with its sleeve and the connection of this sleeve to the chuck carriage.

Figure 5 is a detail plan view illustrating parts that cooperate to enable the length of travel of the surface being refaced, on the abrasive face, and also enabling altering the length of the travel on the abrasive face. In this view pins and bolts are shown in section in the plane of the section, which is just below the under face of the carriage to which they attach the parts that are shown in this view. This view shows the parts in the relation they have at the backor rearward limit of the travel.

Figure 6 is a view similar to Figure 5 and shows the same parts but indicates them located in the opposite extreme position from that from which they are shown in Figure 5. In this view the portion of the plate of the carriage is indicated in a dotted line.

Referring particularly to the parts and especially to Figures 1, 2a, and 2b, the machine illustrated includes a base frame 1, the upper. portion whereof is formed into a guide through the medium of two dove tail guide channels 2 in which slide the key portions 3 for the base slide or sub-carriage 4.

The sub-carriage 4 is provided with transverse guide ways 5 for guiding an upper carriage 6 transversely to the direction in which the guide grooves 2 guide the sub carriage 4. Y Y

As indicated in Figure 2a a rotary grinder preferably has a conical rim 7 with a plane transverse face 8 which also is in a plane perpendicular to the axis of rotation of this grinder, and this face 8 is in a plane parallel to the guiding direction resulting from the use of the guide .channels 2. In other words, when a valve head is held in the chuck and the guiding of the upper carriage 6 occurs along the guide'channels 2, the head being ground will move by a movement of translation along a line parallel to the plane in which the abrasive face 8 lies.

Mounted on the flat upper face 9 of the cariage 6 is a chuck 10 which is shown in detail section in Figure 3.

On the front under face of the base 11 that rests on the.

face 9, the pintle 12 is provided resting in a socket into which it fits. This pintle enables the chuck 10 to be swung around the axis of the pintle to alter the angle through the slot from the upper face 9, and this bolt is provided witha clamping nut 16, having a lever 17 for tightening the same.

Above the location of the chuck 10, as indicatedin Figure 1, an electric motor 18 is provided, one end of which is attached to the vertical frame plate 20, and on the rear face of this frame part a housing 21 is provided for boxing in driving meansfor a tubular chuckjvspindle, as will-be described more fully hereinafter..

It should be understood that theupper carriage 6, supported-as it is on sub-carriage 4 is capable of travelling in two direction. This will now be described.

Referringnow particularly to Figures 2a and 4 to 6 inclusive, the means for regulating the travel of the upper carriage 6 depends partly upon the movement of the sub-carriage 4 along the guide ways 2. In order to accomplish this a rocklever 22 is provided rocking about a fulcrum pin 28 andthis rock .lever is provided withadrivingarm that extends in-a general transverse direction to the guide ways -2; thisrdriving arm has a driving pin for enabling the rock lever 22 to shift the valve-being ground on; the face of thegrinder This rock lever 22 'is, moved to and 'fro. throughthe agency of'a link 23 connected to the rock lever 22 on a large pivot pin connection 24. The driving pin referred to above is preferably in the form of a saddle 25 guided-to slide longitudinally on the driving arm 26 of'the rock-lever and this saddle on its upper side is provided with a pivot pin 27 that connects the saddle to the under side of the sub-carriage 4.

In practicing the invention the rock-lever 22 is mounted on a pivot or rocking point which is capable of being adjusted laterally with respect to the guides 2ifor'the carriage 6; in other words, if this fulcrum pivot for the rocker 22 is moved toward the location of the saddle. 25'

the movement of the saddle by the driving arm 26 will be reduced, giving a shorter travel to the sub-carriage 4, and of course, a shorter travel for the. surface of. the valve head that is being applied to the abrasive face 8; On the other hand, if the fulcrum pin. for the rocker 22 is adjusted in the opposite direction the length of travel or stroke of the surface being applied to the abrasive face 8 willbe increased. The fulcrum pin referred to is preferably in the form; ofa pin or pintle 28 carried on the end of an arm 29 of a bell-crank lever 30; the other arm 31 of which is provided with means for effecting the twoadjustments of the fulcrum pin just, referred to. In order to accomplish this and at'the same. time provide greater, relatively large wearing surfaces the end of the arm 31 is formed with two forks co-extensivelwith each other and: which are provided with aligning sleeves such as the sleeve 32 and the bores of these sleeves carry a pivot-block 33 having atransverse threaded bore 34 to receive a threaded neck 35 on an adjusting stem 36 which stem extends out to the side of the frame 1, where it passes through a bearing sleeve 37 mounted in a roller bearing. 38 set in a suitable bearing casing 39; Beyond this point the stem 36 is provided with a hand wheel 40 with a suitable handle 41 for rotating the stem 36 through shown in Figure 6; but this bracket carries the threaded sleeve 33 as an integral part. This bracket 54:: is like the two bearing brackets,,and carries two integral lugs 4b, that are attached by bolts 53a to the underface of the carriage-6; the threaded sleeve 33,'actually is a sleeveform nut running onthe adjusting screw 46.

Below the sleeve 33, this machine piece is provided with a downwardlyprojecting pin 27 fitting neatly into a drilled socket in a saddle or pivot-block 25. Stop collars 46a ilimit -travel;of block 25'.

The screw 46 is carried on an extension. or rod 47, the outer end of which is, carried in a .thrust collar 48carrred in aball bearing 49.. And theouter end of the extension of stem 47 carries a hand wheel 50 With. a ball form handle 51.;

By rotating the hand wheel 50 shown in Figure 1, it is evident that the threaded sleeve 33 can be moved forward or back on the screw; such a movement will shift the carriage the same amount forward or backward. This, of course, enables the location of the conical face of the head 70 on the abrasive face 8 to be adjusted as may be desired.

When the rocker arm 26 moves to and fro, this rocking movement will be transmitted through the block 25 and pinr27 to-thecarriage andto the valve carried in its chuck.

In order to. provide limiting stops for the amount of adjusting movement that can be made at the threaded neck 35, nuts 42 wit-h-lock-nuts 43 are provided on the same (see Figure 2a).

The ball bearing 49 is mounted in a bracket 52 attached by bolts 53 to the undersides of the sub-carriage 4.

The inner end of the adjusting stem or spindle 47 is mounted rotatably in a bracket 54 similar to the bracket 52 and secured in the same way to the sub-carriage 4 by bolts 55. By rotating the hand wheel 50 it will be evident that the saddle 25 can be adjusted by small in crements of movement forwardly toward the location of the grinder wheel.. In this way the limit of travel of the surfaces being refaced can be set on the abrasive face 8.

In order to' enable the carriage 6 to be shifted on its' guide ways 5 to. move the machine piece being refaced on the abrasive face 8, or to permit it to be adjusted to the same, a hand lever 56 is provided (see Fi ure 2a) which is pivotally mounted at its inner end on a pivot pin 57.0n sub-carriage 4 that provides a ball bearing 58 on the pin. Near its middle portion this lever carries a link 59', one end of which is attached by a ball bearing 60 similar to the ball bearing 58, and the link extends over to a. similar bearing and pin 61 that secures it to a fiat seat face in line-with the face- 62 shown in Figure 1. By seizing the ball. handle. 63-iand moving towards the right the link59awill operate as a strut link to push the carriage 6 towards the right and remove the machine piece. carried. in the chuck from.the vicinity of the grinder 7. A" return spring 64' is provided for the carriage 6 which returns the carriage toward the left and normally holds it so thatthe lever 56 is against the end ofan adjustable stop. 65, the mounting for which is shown win horizontal section: imFigure 2m Initsconstruction this adjustable stop includes a stem 65the endz-of which carries a screw thread 66which is received in the threads 67 on the hub of the hand wheel 68, which. hand wheel is mounted on a ball bearing 69 on a bushing 70 and this bushing has a press fit in the bore 71 of the tubular. head 72 of a. bracket 73, said bracket being secured on an extension 74 of the sub carriage 4 bysuitable fasteners 75.

Theadjusting, stem 65v has a longitudinal groove or key way 76 cutin it. which receives the tip of a small bolt 77 which functions to keep the stem from turning and also operates as a set screw. when tightened up to hold the stem 65 in any position to which it has been adjusted.

Referringnow-particularly to Figures 2a and 3 the machine piece being referred to in thepresent instance isa poppet type valve 78, that is, a valve of verycorrmon form extensively used, having a disc-form body 79 with-a beveledface'80 to-vco operate withthe valve seat in any'situationiwhere the valve is' employed. The valve illustrated has the usual stem 80a on the axis-of the disc. The valve stem illustrated happens to'be provided at its inner end with a reduced. shank 81 carrying an integral head 82 for the stem, the tip of which is provided with abeveled face 83 which facilitates the introduction'of the stem of the .valve intothe chuck 10;

The chuck 10 has an outer casing 84 of substantially cylindrical form having a head 85 at its forward end 'withra bore 86, and a counterhore 87 carrying a tubular spindle 88 the inner end of which is turned down'to form 1 a neck 89 of reduced diameter that passes through twin ball-bearing 90 behind which the neck 89 carries a long thread to receive the threaded hub 91 of a sheave or pulley 92 of cup-form with a rim 93 to enable the spindle 88 to be rotated by a pair of driving belts 94.

Within the forward end of the bore 95 of the tubular spindle 88 is a chuck chamber 96 in which a clamping collet 97 is held. The collet 97 is preferably of 3-jaw usual split type, each jaw having a head 98 at each end extending through approximately l20 degrees of circumference, and adapted at their inner and outer ends to expand resiliently so as to co-operate with two conical restricting bores such as the conical bore 99 of an annular seat 100 attached on the forward end face 101 of the spindle 88 by machine screws 102.

On the outer end of the seat 100 it is provided with means for detachably carrying a gasket 103 of cushion material such as neoprene, plastic rubber, or other compressible cushion material. This gasket constitutes a tapered nose for the chuck with a forwardly constricted bore 104 the rear end of which makes a fair extension surface with the conical seat 99. The entrance to the bore 104 has a convexly rounded lip 105 that co-operates with a machine piece such as the valve 78 to press the outer end of the lip against the inner face of the disc 79 in an annular sealing zone at 106. In other words, the inner convexity of the lip 105 enables it to fit closely into the usual fillet that blends into the side of the stem 80a and the inner face of the valve disc.

Any suitable means may be provided for securing the gasket 103 onto the forward face of the collet seat 100. As illustrated in Figure 3, this means includes a flange 108 on the seat 100, with an annular groove 109 behind it; and the adjacent base portion of the gasket is shaped with a cross-section to fit to the flange 108 and the groove. This form for these parts enables the gasket to be readily removed and replaced by a new one. But the wear on the gasket is slight because it rotates with the machine part such as the valve that rotates in unison with the rotating chuck.

The chuck includes a relatively movable rear seat 110 of tubular form with a conical bore like the conical bore 99 to co-operate with the heads 98. When the valve is held in the chuck 85 the relatively movable seat 110 is pressed forwardly by a relatively strong holding spring 111 the forward end of which thrusts against an annular shoulder 112 formed on the movable seat 110, and the rear end of which thrusts against an inwardly extending flange 113 projecting toward the axis of the chuck atthe inner face of the hub 91 of the pulley, 92.

On the under side and at the forward end of the chuck it is split longitudinally, as indicated at a, and provided with two transverse bolts 114 that can be used to take up wear in the bore 86 and the counter-bore 87.

The inner end of the stem 80a when the chuck has been loaded, lies against the forward end of a piston or cap 115 having a long sleeve-form body 116 that receives the forward end of an ejector spring 117. The parts shown in Figure 3 are in the relation that they have when the surface 80 is being pushed to the abrasive face of the grinder.

The piston 115 slides in a central bore 118 in a relatively movable collet seat 110, and the rear end of the spring 117 thrusts against a threaded plug 119 that screws intothe rear end of this bore.

Referring to Figure 3, it should be understoodthat in performing a grinding operation, the head of the valve 79 is held in the machinists hand and the valve stem 80a is thrustinto the collet with sufiicient force to compress the ejector'spring 117. In doing this the inner face of the valve head displaces the rounded lip 105 of the tip of the gasket 103 toward the left. This, of course, develops reactive compression forces in the gasket effecting the development of a circular sealing zone at which the lip 6 of the gasket is pressed forcibly against the inner face of the valve head.

When completing a refacing operation the valve head should be removed from contact wtih the grinder face 8 by moving the upper carriage 6 to the right of the guide ways 5. (See Figure 2a.) This prevents any injury being done to the edge of the grinding wheel rim 7 if the valve head were moved off the grinding face 8 by sliding it out of contact by crossing the outer edge of the face 8.

The pulley 92 is carried in an annular casing 120 the rear disc wall 121 of which provides a seat for the flange 122 of a cylinder 123 to the forward end of which fluid, preferably compressed air, is admitted through a hose 124. This admission is effected through a port 125 in front of a piston 126 that can travel in the bore 127 of this cylinder, closed at its rear end by a plate-form head 128.

The middle portion of the piston 126 is formed intoa forwardly projecting cylindrical sleeve 129 which slides freely through a guide bore 130 in a transverse wall or head 131 that is integral with the cylindrical wall of the cylinder 123.

The bore 130 and the perimeter of the piston 126 are provided with O-rings 132 of neoprene to seal the same against movement of compressed air past the same.

The rear end of the relatively movable tubular seat 110 for the jaws 97 passes through aligning openings in the rear of the hub 91 and in the forward transverse wall 133 of the body 129 of the piston 126, and within the bore 134 of this body 129 the neck 137 is encompassed by a ball bearing 134a, the forward ball-race of which seats against the rear face of the end wall 133, and the rear ball-race seats at its side against a split ring 135 received in an annular slot 136 near the rear tip of the shank 13-7 of the shouldered movablecollet seat 110.

With this organization of parts it will be evident that when compressed air or other fluid is admitted to the forward end of the bore 127 the piston 126 will travel toward the rear and will draw the collet seat 110 with it. This, of course, will release the three jaws 97 that have been gripping the valve stem 80a whereupon the ejector spring 117 will force the piston 115 forward until it reaches the inner ends of the jaws 97. In this movement it will have ejected the valve which will be held in the hand of the operator as this takes place. The operator will then replace it with another valve and push its stem back until the inner face of the valve head 79 comes against the tip of the gasket 103. While the operator is holding the valve 78 in this position he permits the spring 64 to move the carriage to the left until the lever 56 comes up against the stop 65. When the carriage 6 moves toward the left in this movement the compressed air in the forward end of the bore 127 will be released. The admission of compressed air and its release is accomplished automatically by the movement of the carriage co-operating with a spring-pressed pneumatic valve 147. (See Figures 2a and 4.) Compressed air is admitted to the casing of this pnuema-tic valve 147 by pipe 138 and passes to and from the cylinder through a pipe 139 that connects to the hose 124, and in exhausting passes through the valve 147 to reach the exhaust pipe 140. The valve 147 is normally held in this exhaust position by a coil spring 141. This spring holds the actuating stem 142 of .the valve in its extreme projecting position when the valve is in position to exhaust the air from the bore 127 in front of the piston 126. In this extreme position which is indicated in Figure 2a, the tip of the stem 142 is in position to 'be engaged by a cam face 143 on a cam block 144 on the forward edge of the carriage 6.

The spring 141 is located between the casing of the valve and the collar 145 on the stem. As indicated in Figure 4, when inclined cam face 143 has pushed the stem in as far aspossible, its tiprides on'the' flat face (uninclined) 146, and this holds the valve closure 14711 in the position indicated "in Figure 4. The block-form closure is then in the position indicated in Figure 4, so that the compressed air can flow through the valve closure or casing from the pipe 138 and thence into the pipe 139, but when the carriage 6is in'the'position in which it is shown in full lines in Figure 4 the valve closure 147a will have been 'moved'by' the spring 141 toward thecarriage 6 and an inclined passage 148through it will connect the pipe 139 to'the. pipe 14%"; which e1 hausts the air from the cy1inder'123.

The rear end face 149 of the casingSSofthe chuck 10 is secured against the adjacent face of the frame'pla-te 20 already'referred to and to whichit'is'secured by long bolts in the form of machine screws'l5tl (see Figure 3), the heads of which are counter-sunk into a keeper ring 151, the inner face of which is counter-sunk to receive the adjacent outer race-way of one of the twin ball-bearings 90. The face 149 is provided with a'counter-bore 152 to receive the outer ball-race ofthe'adjacent twin ball-bearing '90 and the bottom of this counter-bore is in line with a shoulder 153 so as to form a'seat for the corresponding inner ball-race.

The frame plate 2% of course, is providedwith an opening or bore 154 of the same diameter as the counterbores in the keeper 151 and the counterbore 152.

It should be understood that in operating this refacing mechanism the over-travel of the valve headon each stroke, beyond the adjacent edge of the abrasive face tends to prevent wearing the abrasive face'out of its true plane, but it will of course, be'necessary to dress this face from time to time.

In order to accomplish this I provideadiamond' point 155 (Figure 2a) on a stem 156 adjustablyheld on the end of an arm 157 to swing about a'stud 158yand rigid with a handle lever 159 which enables the diamond to be swung up to its dressing position.

23- to give the diamond travel to and fro completely across the width of the abrasive face.

Referring now to Figure 2b, the'drive for the link 23 is shown through a broken-away portion of'the housing 163. This driving means includes a worm 164 on awormshaft, whose meshing worm-wheel 166 carries crank-pin -167 eccentric to the ball-bearing 168 of the'worm-wheel.

The worm-shaft carries a rigid belt pulley driven by a drive belt 169 of tapered cross-section, from a small driving pulley 170 cast integrally with a larger pulley 171 with twin grooves 172 the belts 173 of which drive the grinder shaft 174 running in two twin roller-bearings 175 and 176, the latter of which is a thrust bearing for taking the thrust of the refacing grinder 183 that 'has the rim 7 and the abrasive'face 8 described heretofore.

The thrust bearing 176 is backed up by a thrust ring 178 with drilled spring chambers extending in from its rear end, that house a plurality of coil springs 179. The rear ends of these springs seat against a collar 180 bolted within the bore 181 of the tubular casing 182 that houses 'both the twin bearings.

The grinder183 is carried on the forward end of the shaft 174 to which it may be se'cured'by a'conventional lead center 184 clamped up by a'nut 185"seating on a washer 186. The ends of the long drum 187 form seats for the inside ball-races 188. 'The lead center -184-seats up against a spacer collar'189"between"it and -8 the adjacent insideball'race 190 and located in a clearance counterbore in a guard casing 191 for the grinder.

A nut192 on the end of the shaft 174 clamps the drive pulley 193 up against a space'collar that seats up against the adjacent inside ball race 194 like the spacer 189, and is located in a clearance opening in the inner headplate'195 in the housing 196 for the belt pulleys and belts already described.

'I'he'four electric switches 197a, 197b, 1970, and 197d, are for closing circuits for the motors employed including the main motor 198, the shaft of which carries the double pulley 170, 171 and the motor 18 that drives the chuck.

Many other embodiments of this invention may be resorted to without departing from the spirit of the invention.

I claim as my inventionand desire to secure by Letters Patent:

1. In a valve-refacing mechanism for grinding a conical face on a valve, the combination of a rotary grinder mounted for rotation about an axis, and having an abrasive face located in a plane disposed transversely to said axis, a chuck carriage means for guiding the same to move by a movement of translation, in a plane parallel to the plane, in which the said abrasive face lies, a chuck carried by the carriage for rotatably holding the valve to be refaced, with an element of the said conical face lying substantially parallel to the said abrasive face, means for effecting a lateral movement of said guiding means in a direction to bring the said conical face into contact with said abrasive face, and power-actuated means for imparting a reciprocating movement to said carriage by a movement of translation in which the element of the conical face of the valve adjacent to the abrasive face moves in a direction parallel to the abrasive face to cause the conical face of the valve to travel'to and fro on the abrasive face.

2. Avalve refacing mechanism according to claim 1, including means controlled at will by the operator of the mechanism for regulating the length of'thetravel of the valve to and fro on the abrasive face.

3. A valve refacing mechanism according to claim 2, in which the means for regulating the length of the travel of the carriage includes a rock-lever having a fulcrum pin and an arm'extending from the fulcrum pin and transversely to the plane of the said abrasive face, a pivot-block adjacent to the carriage, said arm having a sliding connection to said pivot-block operating to enable the arm to move to and fro with respect to the pivot block to effect a reduction or increase in the distance between the fulcrum pin and the block when the said arm carrying the fulcrum pin moves toward or away from the pivot block, thereby enabling the travel imparted to said block by the rocker arm to be increased or'reduced; and a pivot pin whose axis is parallel with the axis of the fulcrum pin pivotally mounted in the block; means including a threaded sleeve carrying the said pin; an adjusting screw carrying said sleeve; and means for mounting said screw on the carriage with its axis disposed in a plane extending at right angles 'to the said abrasive face of the grinder.

4. A valve refacing mechanism according to claim 3, in which the said screw is provided with an actuating shaft leading to the operators station, with a hand wheel attached to the same for the operators use.

5. A valve refacing mechanism according to claim 1, including means controlled at will of the operator for shifting the location of the travel of the valve face with respect to the abrasive face.

6. A valve refacing mechanism according to claim 1, including means for yieldingly biasing the guiding means for the carriage to move' the valve face into engagement with the said abrasive face, a stop for, limiting the movement of .the carriage toward'the grinder member, and means for altering "theetfective position of said stop'to control the amount of material that can be removed from the valve face in the grinding operation.

7. A valve refacing mechanism according to claim 1, in which the said means for moving the valve face against the abrasive face includes a lever operatively connected to the guiding means for the carriage for moving the same in a direction to withdraw the valve face from the abrasive face; and a stop in the path of movement of said lever for limiting the movement of the carriage in the direction to bring the valve face into contact with the abrasive face.

8. A valve refacing mechanism according to claim 5, including a spring operatively connected to the carriage for biasing the carriage in the direction to apply the valve face to the abrasive face.

9. A valve refacing mechanism according to claim 1, which includes means for regulating the length of the travel of the carriage, including a rock-lever with a fulcrum pin, said rock-lever having an arm extending transversely to the plane of the said abrasive face, a pivot block on said arm and operatively connected to the carriage to impart to it the traveling movement from said lever; and means controlled at the will of the operator for supporting the said fulcrum pin, and for shifting the same toward or from the said block to regulate the effective lever arm for moving the block and its radius from the fulcrum pin, and thereby to regulate the travel of the valve face across the grinder face.

10. A valve refacing mechanism according to claim 7, in which the means for supporting the fulcrum pin includes another lever on the carriage with a thread connection for actuating the same at the will of the operator for regulating the amount of shifting of the fulcrum pin toward or from the said pivot block.

11. In a mechanism for grinding a conical valve face,

the combination of a rotary grinding wheel having a flat abrasive face disposed in a plane extending at right angles to the axis of rotation of the grinding wheel and mounted to rotate in a fixed plane, means for imparting variable travel to the valve to be ground with its conical valve face touching tangentially said flat grinding face, said means comprising a carriage, means for rotatably supporting the valve on the carriage, a relatively fixed guide-member for guiding the carriage to and fro in a direction to cause the conical valve face to travel across the flat abrasive face in a direction parallel to the plane in which the abrasive face lies, means including a lever, having an arm with a fulcrum pin thereon, a rock-lever pivotally mounted on the fulcrum pin, a pivot block guiding the driving arm of the rock-lever, a pivot pin supported at the underside of the carriage, said driving arm slidably connected onto the pivot block, means associated with said first named lever for imparting the travel movement to the carriage to shift the contacting face of the conical head of the valve along the line of tangency by a movement of translation in the same plane as the flat abrasive face of the grinder wheel, and hand controlled means for adjusting the position of the pivot pin under the carriage to alter the location of the travel on the grinding face.

12. A valve refacing mechanism for grinding a valve face, comprising a rotary grinder element mounted for rotation on its axis and having a fiat abrasive face disposed transversely to the axis of rotation of the grinder element, means including a carriage with means for supporting the valve with its seating face to be ground, touching, and tangent to, the flat abrasive face, means for guiding the carriage in a direction to shift the valve face across the abrasive face, an actuating lever having a relatively fixed pivotal support and having a driving arm extending transversely to the said guiding direction, a driving connection from said driving arm to said carriage including a power driven part pivotally mounted with respect to the carriage, carried by said driving arm, and capable of relative shifting movement along the driving arm; means 'for rocking said lever to rock the driving connection and reciprocate the carriage in the said guiding direction to impart travel movement to the said carriage and the valve face, and to shift the valve along its line of contact on the abrasive face; and means operatable at will of the operator to shift the pivotal support for the actuating lever toward or from said driven part carried by the carriage, and thereby controlling the amplitude of travel of the valve face. I

13., A valve refacing mechanism according to claim 12, in which the said pivotal support for the actuating lever includes a lever carrying the same, and means controlled at the will of the operator for orienting said last named lever through slight increments of movement to regulate the amplitude of the travel movement of the valve face.

14. A valve refacing mechanism according to claim 13, in which the means for rocking the actuating lever includes a link attached to the same, with means for reciprocating the link; and means operatable at will of the operator for shifting the said driving member on the carriage through slight increments toward and from the abrasive face to regulate the location of the travelling movement of the valve face on the said abrasive face.

15. In a chuck assembly for holding a valve that has a stem, to present the valves head to a refacing grinder or the like, to perform an operation upon the same, the combination of a carriage, a chuck casing on the carriage, and having a bore within the same with a relatively fixed substantially conical seat at its forward end, said assembly including a collet with jaws biased resiliently toward an open position, carried within the casing for holding the valve stem in the chuck, a relatively movable tubular member With a conical seat located toward the rear end of said bore, a coil spring biasing said movable tubular member toward the forward seat, said jaws having split end collars to come against said seats so as to constrict them and grip the stem of the valve between the same, a pneumatic device including a cylinder for actuating the movable tubular member, with means for admitting compressed air to the cylinder, including a relatively fixed pneumatic valve, a manually operated handle operatively connected to the carriage for moving the same, said carriage having a cam for engaging the relatively fixed pneumatic valve to actuate the same when the carriage is moved to place the valve head out of contact with the abrasive face, thereby admitting compressed air from the said pneumatic valve to the cylinder, for effecting the withdrawal of the shouldered tubular member to remove its inclined seat from contact with the adjacent end of the collet against the force of said spring to release the jaws; and an ejector spring mounted coaxially in the chuck casing with a sleeve-form piston on the forward end of the ejector spring adapted to be moved rearwardly by the insertion of the stem of said valve when the same is inserted through the forward end of the chuck and between the said jaws, said ejector spring operating to eject the said valve after the said jaws have become released.

16. A chuck assembly according to claim 15, including a shouldered tubular member towards the rear carrying the said movable seat at its forward end, and having a shoulder against which the first named spring thrusts, said tubular member having a bore with a sleeveform piston within the same adapted to be forced back by the end of the stem of a valve when the stem thereof is inserted in the chuck, said shouldered tubular member having a thrust head fixed therein at its rear portion to receive the thrust of the ejector spring when it is compressed by the inward movement of the stem of the said valve, thereby imparting movement to said tubular member, and compressing the first named spring sufliciently to further separate the two seat faces for the ends of the collet, and thereby enabling the jaws to open automatically to receive the stem of another valve.

-17. A chuck; assembly according to claim 15 includand thereby exclude the detritus'from' there'facing op- "eration upon said valve head from passinginto the interior'of the chuck.

18.'A chuck assembly according to claim 15, in which thenose-of the gasket has a tapered-tip at its forward end, capable of being jammed against the inner face'of 'the valve head being refaced by the machine,'whileheld in the chuck.

19. In a valve refacing'mechanism for "holding a valve stem when applying the valve head carried thereby to a refacing grinder wheel, the combination "of a chuck-cas 'ing having an annular seat with a conical'seat face .at its forward end, and having an opening therethrough to receive the valve stem-when thrust intothe same from the front, a collet within the chuck-casing having a split collar at each end with 'bars'connecting the split collars "and biasing the collet toward an expanded state to permit the insertion of the stems of the valves that are to be -refaced; a tubular spindle rotatably mounted in the chuck casing, a tubular seat member mounted to slide in the bore of thetubular spindle,'having a conical seat face at its forward end, a holding coil spring surrounding the seat member with means for taking forward thrusts from said holding spring and transmitting it to said seat member, an ejector spring within the bore of the seat member "having a piston-type cap'for imparting thrust from the inserted stem to the ejector spring for compressingthe same by manual force applied through the head of the valve, a rotary driving member connected to'the rear end of the said spindle for rotating the same, means for providing a seat for the rear end of the holdingspring,

a carriage on which the chuck-casing is mounted; means for supporting and guiding said carriage for effecting contact between the valve'head and the. grinder wheel, and withdrawing the valve'head from the grinder wheel, a fluid operated power cylinder having a. piston con- "nected to the rear end of, said seat member, means for maintaining the cylinder andits pistoniin an inactive state when the carriage is holding the valve head against the grinder wheel, automatic means'for supplying fluid under pressure to the cylinder activated by the moveiment of the carriage when withdrawing the valve head from the grinder wheel, and thereby. effecting the withdrawal of the seat member and its conical seat from its adjacent end of the collet, soas to. permit the collet to expand and freeithe stem from its grip, whereupon the "ejector spring lengthens to effectthe ejection of the valve stem and valve fromthe collet and the chuck-casing.

20. A valve refacing mechanism according to claim 19, in which the automatic means for controlling the fluidi fromthe cylinder, .and in which. cam means on the carriage-'shiftsthe said valve mechanism to a second position that releases the'operating fluidfrom'the cylinder.

'21. A grinding machinefixture for supporting machine parts that have a head to be ground and a stern integral 'with said head, said fixture having'a chuck casing for :supporting a collet 'with jaws for clamping the stem of "the part to be ground, said fixture including a gasket with a cuneiform'body composed .of-resilient compressible "cushion material having an end of relatively large transverse dimension, said cuneiform body having an'opening therethrough coaxial with the collet and also having .a tapered tip of relatively small diameter at its forward end with an opening through which the stem of the machine part to be ground is thrust into the collet, the small end of said body having a convex face adapted to be compressed and held in compression when the stem of the machine part is introduced, with the innerface of the head pressed tightlyagainst the tip of the gasket, thereby effecting a circumferential seal in an area surrounding the stem and sealing otfthe opening through the,ga'sket,

thereby preventing the entrance of the detritus occasionedby the grinding operation from passing into the interior of the chuck casing.

22. Means for holding a machine part having a stem .and a body with a transverse face adjacent the stem for the performance of a machine operation upon thetmachine part, the combination of a collet casing, a collet mounted within the casing and having clamping jaws for clamping the said stem after being introduced through the collet, a gasket mounted on said casing coaxially with said collet and located in front of the collet, said gasket composed of resilient compressible cushion material and having a tapered forward end with an opening through the tip to receive the stem, the tip of saidgasket operating'to be compressed whenthe stem.of the machine part is introduced through the same and pushed inwardly by the operators hand, thereby developing com- -pression, forces at the said tip. establishing an annular sealing zone on said transverse faceforexcluding detrltus from the said machine operation.

References Cited in the file of this, patent UNITED STATES PATENTS 109,325 :Knight Nov. 15, 1870 678,172 .Grist July 9, 1901 1,186,616 Strecker June 13, 1916 1,202,400 McCullough Oct. 24, 1 916 1,467,023 Willson Sept. 4, 1923 1,602,135 Tryon Oct. 5, 1926 1,655,821 Rich Jan. 10, 1928 1,853,907 Kriesel Apr. 12, 1932 1,908,946 Barber May 16, 1933 1,916,775 Steber July 4, 1933 2,060,396 Klein Nov. 10, 1936 2,086,052 Silven July 6, 1937 2,108,311 Harris Feb. 15, 1938 2,113,387 Silven Apr. 5, 1938 2,136,188 Gagne etaal Nov. 8, 1938 2,259,883 Gleba Oct. 21, 1941 2,376,594 Hite May 22, 1945 2,606,767 Preston Aug. 12, 1952 2,671,293 -Grobey Mar..9, 1954 

